Fast Idle on start up cold engine (Ohio Winter) is going up to 2500rpm is this too high?

Hi, not sure where you are but i'm surrounded by these [in nz], must be an illness, RH drive by the way but anyway hope this help from my personal experience & had to more or less work it out for myself by following airways through. [Cold] Fast idle seems to be controlled mostly if not totally by a thermostat controlled airway to the inlet [somehow]. LH side & has two small screws holding a flat plate over access to a plastic tapered item that can be screwed clockwise to set it nearer the thermostat controlled tapered thingy that is pushed up until it eventually cuts off the air which then is totally controlled by the idle speed air adjustment. Just altered one of mine & rotated it a turn which was enough but may need more. My other car which has the 2.5 G25a motor [identical to the G20a] I adjusted years ago but is creeping back up so possibly that little thermostat is faulty & not lifting it soon enough or the threaded plastic thing has wound back a bit as has nothing stops it except thread tightness as such. Has a two opposing slots for two screwdrivers & drag it around or what I did was use my expanding circlip pliers & turn it. Good luck.
Ps, Tried to attach a photo from the net but won't work so will give the address. Flat plate lines up with the letter F above in one of the bright lower photos & is just below the accelerator cable--[you'll see it], nothing 'jumps out' when you take that plate off, just covers the access to the adjustment ring. Also from the pic you can imagine a small thermostat to lift the shut of plastic taper thing in the lower section. OK, ebay auction 350690698569. Thanks. M.

Sorry, not sure why but has changed or added the word 'amp' for some reason, don't know whats going on there but you'll work it out. Cheers M.

Sorry about that, shows I wouldn't know what year it is haha. Reason I ended up here is--my 1992 g20a vigor has an unusual noise when warming up. Sounds like two meshing gears lacking oil & is somewhere in the front [i think]. Have replaced the cam belt tensioner bearing with an ok spare plus flicked the seals out & greased it. Ran it minus the balancer so no pulley/tensioner bearings, no alternator [might try that again]. Only thing turning was water pump [which it doesn't really sound like]. Not sure if there's an electric fuel pump under the inlet manifold as sound a bit like under there--hard to pinpoint. Not a big problem as car is parked up now with a cracked windscreen but just annoys me that I can't easily diagnose it. Still runs great but on start up from cold you're sort of waiting for something to lock up but slowly goes away. Is ok for the rest of the day I think. [If something finally breaks that'll pinpoint it !]. The noise come to think, is much like my little old lathe when in the extra slow gear & complaining for a squirt of oil between them. On the car, I can't think of anything geared as such. I know noises travel & lying under the front i'm now thinking sounds like in the sump but what? As nothing I can think of, only shell bearings & oil pick up. Don't loose any sleep over it. Thanks, M.